Then maybe you should develop games? Honestly, I can't fault the companies sometimes, we treat the hardware like they're equal on capabilities and work the same. They don't. The only way for a ps3 to keep up with the 360 graphically is to take advantage of the cell, which is going to make programming it entirely different from the 360 version. Sure, it would be awesome if every game was equal, but when it comes to designing a game based around every intricate detail of one set of hardware and then asked to make it work exactly the same on something of a similar tech level, but completely different, I really can't say I'm surprised there are slipups here and there. The developers are human, and in this case it was a separate team from a different company(sort of) trying to do this probably in a short amount of time.
I'm a software developer. I don't develop games, but I understand the issues that come up when you are programming for two separate systems. It's like programming something for the Mac and the PC. Of course, it will never be an exact port, where both run exactly the same, but if you take a piece of software developed for a mediocre machine (XBox 360), run it on something that's more powerful (PS3), it should run at least roughly as smooth as it does on the more powerful machine. If you have to reduce textures, and the framerate is STILL slower than the XBox, to me, that just means you took some auto-converter, translated whatever code you had for the XBox, and fixed any bugs that arose. To me, that means you did absolutely NO optimizing for the PS3.
That being said, I enjoyed the demo very much, but if they did some optimizing, it would warrant me going out and getting this on release day for $60. I looked closely at the demo, playing it for the third time, and realized that the game looks like a PS2 game, and I've been too mesmerized by her beautiful ass the whole time to care.